A dishwasher is a device that removes filth, such as food waste, from dishes or cooking tools (hereinafter, referred to as ‘objects to be washed’) using detergent and wash water.
A dishwasher generally includes a tub having therein a washing space, a rack provided in the tub for receiving objects to be washed, a spray arm for spraying wash water to the rack, a sump for storing wash water, and a supply channel for supplying the wash water stored in the sump to the spray arm.
In general, the dishwasher uniformly sprays wash water to objects to be washed, such as dishes, while rotating the spray arm for spraying the wash water to wash the objects. In recent years, there has been developed a dishwasher further including an auxiliary arm configured to roll along an arc track of a spray arm in order to spray wash water, in addition to the spray arm, which is configured to spray wash water during the rotation of the spray arm using rotational force generated when the spray arm rotates.